Pelvic health for men and women is a medical area of increasing importance, at least in part due to an aging population. Examples of common pelvic ailments include incontinence (e.g., fecal and urinary), pelvic tissue prolapse (e.g., female vaginal prolapse), and conditions of the pelvic floor.
Urinary incontinence can further be classified as including different types, such as stress urinary incontinence (“SUI”), urge urinary incontinence, and mixed urinary incontinence, among others. Urinary incontinence can be characterized by the loss or diminution in the ability to maintain the urethral sphincter closed as the bladder fills with urine. Male or female SUI generally occurs when the patient is physically stressed.
A sling may be used to treat incontinence and prolapse. These slings typically comprise a central portion that is adapted to support the urethra, two end portions bracketing the support portion, a protective sheath or sheaths encasing at least the end portions, and connectors at the ends of the sling. Various ways of attaching sling ends to sling implantation tools are disclosed in U.S. Pat. Nos. 7,364,541 and 7,500,945; and U.S. Patent Pub. No. 2005/0250977, the entireties of which are herein incorporated by reference. Sling implantation tools are employed to form tissue pathways extending, for example, from a vaginal incision to one more abdominal skin incisions.
Tension in the sling is typically adjusted during an implantation procedure in a manner to take up slack in the sling, impart desirable and efficacious tension, and position the supported tissue. For example, sling tension is typically adjusted at implantation sufficiently to take up any slack in the sling and impart at least a degree of increased tension to the urethra with the bladder empty. Alternative tension adjustment techniques that may be employed during implantation are disclosed in the above-referenced patents and publications.
Typically, such slings are fabricated of a loose weave sling fabric or mesh that acutely engages tissue and encourages tissue ingrowth along the pathway through mesh pores to achieve chronic stabilization or “self-fixation.” Tissue ingrowth takes about 2-3 weeks in the typical patient in the absence of any significant intentional or unintentional movement of the mesh. During this post-operative time, the patient monitors the degree of success achieved in ameliorating leakage and any discomfort that might occur if the applied tension is so high as to unduly slow voluntary urination. If any such problems occur, it may be necessary to reopen the incisions to access and pull on the sling ends to tighten the sling central portion around the urethra or to reopen the vaginal incision to pull on the sling central portion to loosen the sling central portion around the urethra. Several approaches have been taken to simplify or reduce the need for such post-operative adjustments.
One tension adjustment complication arises from the fact that the loose weave sling mesh inherently stretches and elongates when tension is applied at the ends or tissue support portion to overcome resistance of the tissue bearing against the sling mesh along the tissue pathway. It is difficult to judge just how much tension to apply to achieve adequate tightening or loosening in the tissue support portion. An elongated repositioning means, e.g., an elongated inextensible tensioning member, may be incorporated, said means extending in or along the sling mesh from near the sling ends to or through the sling central portion. Tension applied to the repositioning means is transmitted along the length of the sling so the sling mesh does not substantially stretch during initial positioning and any repositioning during the acute healing phase.
Other approaches that enable increasing tension of the sling central portion against the urethra involve shortening the lengths of the sling end portions. Mesh folds are formed in the sling end portions using filaments that extend through vaginal incisions externally of the body. Depending on the embodiment, the mesh folds can be released to decrease sling tension or be tightened to increase sling tension by pulling on the filament ends following the initial implantation procedure. In other embodiments, filaments are extended substantially through the lengths of the sling end portions and extend from the vaginal incisions. The filaments may be gripped and pulled to tighten the mesh in the sling end portions to increase overall sling tension.
In still another approach disclosed, for example, in U.S. Patent Pub. No. 2006/0058574, the entirety of which is herein incorporated by reference, a mesh sling or tape is further modified to include a mechanical adjustment means to adjust the length of the tape in the end portions on either side of the central portion after the tape has been implanted in the tissue pathways. The mechanical adjustment means may incorporate a tie-wrap mechanism or sutures and one-way suture retaining devices of the type disclosed in U.S. Pat. No. 5,669,935, the entirety of which is herein incorporated by reference, wherein said means is located along the tape on either side of the central portion. In each case, one suture end is affixed to the tape and extends along it and through a suture retaining device affixed to the tape closer to the central portion. The sutures or tie-wrap are not tensioned at implantation, and the tie-wrap or suture free ends extend through the vaginal incision. If the tension on the urethra is too light as determined during the acute healing phase, the surgeon may grasp and pull on the tie-wrap or suture free ends to shorten the lengths of the tape end portions and thereby increase sling tension. The exposed suture or tie-wrap ends may be severed during chronic implantation.
In yet another approach, tape or sling ends or the end of a tensioning cable coupled to a urethral support mechanism are coupled to a tensioning device that is chronically implanted subcutaneously and can be accessed to adjust sling tension. See, for example, commonly assigned U.S. Pat. Nos. 4,969,892; 5,474,518; and 6,117,067, the entireties of which are herein incorporated by reference. Ratchet or gear mechanisms that are accessed using a driver inserted through the skin and thereby rotated to increase or decrease sling tension are disclosed in the '892 and '518 patents. The adjustment forces are applied to the sling ends and must be transmitted through the sling to effect any change in tension along the sling central portion adjacent the urethra.
Further sling tension adjustment and maintenance techniques involve adding tensioning filaments to the sling free ends and extending the elements through the skin incisions and into engagement with buttons or pads implanted subcutaneously engaging a muscle or rectus fascia layer and/or having tissue engaging elements or anchors along the filament that engage subcutaneous tissues as disclosed, for example, in U.S. Pat. Nos. 6,911,002; 8,518,061; and 8,628,465, the entireties of which are herein incorporated by reference.